Accelerator-driven neutron source for cargo screening

Abstract

Advanced neutron interrogation systems for screening sea-land cargo containers for shielded special nuclear materials (SNM) require a high-yield neutron source to achieve the desired detection probability, false alarm rate, and throughput. The design of an accelerator-driven neutron source is described that utilizes the D(d,n) 3 He reaction to produce a forward directed beam of up to 8.5 MeV neutrons. The key components of the neutron source are a high-current Radio Frequency Quadrupole (RFQ) accelerator and a neutron production gas target. The 5.1 m long, 200 MHz RFQ accelerates a 40 mA deuteron beam from a microwave-driven ion source coupled to an electrostatic Low Energy Beam Transport (LEBT) system to 6 MeV. At a 5% duty factor, the time-average D + beam current on target is 1.5 mA. A thin entrance window has been designed for the deuterium gas target that can withstand the high beam power and the 2-3 atm gas pressure. The source will be capable of delivering a flux >1·10 7 n/(cm 2 ·s) at a distance of 2.5 m from the target and will allow full testing and demonstration of a cargo screening system based on neutron stimulated SNM signatures.

Simulation Study on 104 MHz Radio Frequency Quadrupole Accelerator

“…For RFQ cavity having N basic resonant cells, the relation between the total R, L, C, I and corresponding values of single cell R cell , L cell , C cell , I cell will be R=R cell /N, L=L cell /N, C=NC cell and I=NI cell (2) when ignoring the end effect. Combining (1) with (2) we find…”

“…Radio frequency quadrupole (RFQ) accelerator has been widely used in beam injector, neutron source, etc [1,2]. The two main aspects when designing a RFQ are beam dynamics and RF structure [3][4][5].…”

Crystal growth of organic compound from the melt

“…The main motivating force for the engagement of nuclear energy derived from the projected increment rate of global energy consumption. Harvest of nuclear energy will potentially meet the demand and the process will not release carbon related pollutants to the atmosphere [4,[123][124][125]. Technique involving fast neutrons detection depends on the recoil particles measurement [19,20,60,79].…”